Figure 2. p53 Exerts its Antiaging Effects in Skeletal Muscle and Fat of BubR1^H/H Mice through p21.

(A) Incidence and latency of lordokyphosis in mice of the indicated genotypes.

(B) Average muscle fiber size of gastrocnemius and abdominal muscles of 6-week-old mice.

(C) Skinned 6-week-old BubR1^H/H, BubR1^H/H; p53^−/−, and BubR1^H/H;p21^−/− mice. Note the profound lordokyphosis (black dotted line) and the markedly reduced adipose depots in the BubR1 progeroid mice lacking p53 or p21 (yellow arrows and hashed area). Scale bar represents 1 cm.

(D) IAT (left) and body weight (right) are both reduced when p53 or p21 is lost from 6-week-old BubR1 hypomorphic mice.

Data in (B) and (D) are mean ±SD (n = 5 mice per genotype). Asterisks denote significant changes from BubR1^H/H values. **p < 0.01; ***p < 0.001. See also Figures S1 and S2.